Discovered why she stalled randomly on me yesterday. Examined the nasty scrape and dent caused by me heroically charging in reverse straight into my roommate's car (luckily it missed the newly painted rear fascia or I'd have just about died..)
I honestly do not recall using a plastic inline splice to feed the ECU. Maybe the madness that caused my PO's mods has infected me. Tomorrow sees a proper soldered connection + bullet connector for ease of removal.
Not a good week. I get to save up to take her to DMC Florida now.